1. Field of the Invention
The present invention relates to a silver halide color photographic light-sensitive material and an image forming method using the material and, more particularly, to a silver halide color photographic light-sensitive material having good color reproducibility and graininess and an image forming method using the material.
2. Description of the Related Art
In recent years, a sensitivity and an image quality of a color photographic light-sensitive material have been improved to meet the needs of users. The improvement in image quality has been promoted mainly by improving color reproducibility, sharpness, and graininess. These factors are very important in discussing the performance of a light-sensitive material, so it is obvious that they must be further improved in future.
Formation of a dye image in a silver halide color photographic light-sensitive material is normally performed such that an aromatic primary amine color developing agent is oxidized when it reduces silver halide grains in an exposed silver halide color photographic light-sensitive material, and this oxidized form of the color developing agent causes a coupling reaction with couplers which have been contained in the silver halide color photographic light-sensitive material. Since color reproduction according to subtractive color processes is performed in the silver halide color photographic light-sensitive material, three types of couplers for forming yellow, magenta, and cyan dyes are normally used.
Since color dyes formed by yellow, magenta, and cyan couplers used in a conventional silver halide color photographic light-sensitive material have unnecessary side absorption, color reproducibility tends to be degraded. Therefore, as a technique of improving color reproducibility, a coupler capable of forming a color dye which causes less side absorption has been studied.
Recently, improvements in a hue of a magenta color obtained by the use of a pyrazoloazole-based magenta coupler, in place of a 5-pyrazolone type coupler which has been conventionally used, have attracted attention. An azomethine dye formed by a reaction between this coupler and the oxidized form of a color developing agent has a high saturation because it has little side absorption harmful for color reproducibility near 430 nm and is therefore preferred in terms of color reproducibility. Examples of the coupler of this type are described in U.S. Pat. No. 3,725,067, JP-A-60-172982 ("JP-A" means Published Unexamined Japanese Patent Application), JP-A-60-33552, JP-A-61-72238, and U.S. Pat. Nos. 4,500,630 and 4,540,654.
Since, however, these couplers have a very high efficiency in color formation, sensitivity and graininess are largely degraded in a material for photography, particularly a color reversal light-sensitive material. For this reason, these couplers cannot be put directly into practical use. To solve this problem, it is possible to employ a method of using a 4-equivalent coupler having a low equivalence as described in JP-A-63-153548. However, a light-sensitive material using a 4-equivalent pyrazoloazole coupler is still inferior to that using a pyrazolone type magenta coupler in sensitivity and graininess.
In a color photographic light-sensitive material for photography, in order to adjust gradation in designing a desired characteristic curve and to meet the need for a high image quality by mainly improving graininess, a light-sensitive layer sensitive to one color is generally constituted by two or more emulsion layers having different sensitivities. However, although the pyrazoloazole-based magenta coupler can improve color reproducibility, graininess is degraded when it is used in an emulsion layer having a high sensitivity. Therefore, a certain solution for this problem has been desired.
JP-A-63-311252 or JP-A-1-131560 describes that graininess is improved by the use of a coupler for releasing a scavenger for the oxidized form of a developing agent in combination with the pyrazoloazole-based magenta coupler. If, however, a light-sensitive layer has a multilayered structure constituted by two or more layers, this method is still unsatisfactory to improve both the graininess and color reproducibility of a green-sensitive layer. That is, the aspects of the present invention are not described in detail in these patent specifications.